You can now tell the SQL Server installer to include Service Packs (SPs) and Cumulative updates (CUs) and patches as part of the initial install so that only one installation has to be run to create a new instance that is up to date to a certain build level. No need to slipstream the build to a certain level before-hand.

Support for a new type of Windows service account that has its password managed by the domain controller rather than administrators. This means no more password changes and nobody knows the password so it is more secure.